Rotary pivoted hammer



iig-April 2 2, 1924; n 1,491,418

H. M., PLAISTED ROTARY. PrvoTED-.HAMMER Filed-'April l2., '19243 @La h1.

HAROLD M. PLaIs'rnn, or s'i. LoUIs, IarssoUnI, .assIonon "ro WILLIAMS :sannita coiaraNY, or sr. L oUIs, raissonnI, n conronnrron cr cnnsnnn a rnnvnnrznn MISSOURI.

ROTARY PIVOTEB HAMMER. v.

To all whom #may concern Y Be it known that I, HAROLD M. PLaIs'rnn, a citizen of the United States, residing at St. Louis, State of Missouri, have invented certain new and useful Improvements in Rotary Pivoted Hammers, of which the following is a specification.

This invention relates to certain new and useful improvements in rotary pivoted hammers for pulverizing grain, rock, and other material, the peculiarities of which will be hereinafter fully described and claimed.

The main object of my invention is to provide a reversible insert piece for a rotary pivoted hammer that is adapted to present four cutting edges or points in suc-V cession to act on the material being reduced, and to expose only one cutting point while protecting the other three points from Wear until they are successively adjusted to the operative position; and secondly, to mount said piece detaehably yet firmly in eiect-ive position in the head of such a hammer.

In the accompanying drawing on which like reference numerals indicate corresponding parts7 Fig. l represents a side face view of a hammer exemplifying my invention mounted on a rotor shaft in connection with a concentric cage; Fig. 2, an edge view of the same showing the adjacent parts in section on a radial line from the center of the shaft through the pivot of the hammers; Fig. 3, a detail side face view of my four point insert piece, and Figs, an edge view of the same as adapted to a relatively thin hammer.

1 designates a rotor shaft carrying discs 2 and hammer rods 3 on which are pivoted rotary pivoted hammers consisting of Shanks s, preferably relatively thin compared to their width, and having a recess 5 at the head end in which is mounted an insert piece 6 of finer grade of steel and having multiple points that are successively brought to operative position.

The recess 5 divides the headend into front and rear jaws 7 and 8 respectively, the front jaw being shorter than the rear jaw so as to expose the operative point 9 of the insert piece and the adjacent edge surface 10 forming the front throat. A rear point 11 pairs with the point 9 of the insert piece, and a corresponding edge surface l2 reversely inclined to the surface 10, forms a widened or dove-tail end on the insert piece at the outerend, which is 'duplicated by an- Y other pair of points 13 and 14: on the inner 1 dove-tail end. The edge surfaces 10 andl are preferably located in cylindrical planes that are nearest to each other'at the middle of the piece, and diverge in both directions to form the dove-tail ends and constitute cutting points before mentioned where they intersect the outer and inner end surfaces 15 and 16 respectivelyA of thefsaid dove-tail" ends, which are preferably curved as shown vin the side face'views Figs. 1 and 8. TheV longitudinal axis X of the insert piece and the corresponding recess in the head,V is incllned backward with regard tothe direction of rotation indicated by the arrow 17, Fig.

1, so that suitable clearance is provided.y for the outer edge surface, and the rearj aw 8 is alined therewit The curved edge surface 10 of the point 9V preserves the acute angle of the point in the tippedback position shown. Y Y

This insert piece is secured in `any suitable manner in said recess, preferablyV by providing notches 18 and 19 in the edge surfaces of the recess and insert piec'erespectively which match to receive fastening riv ets 20, preferably countersunk at the ends, Y

and maintain the said piece from lateral displacement. The'recess and insert piece are normally located in the radial plane Y through the rotor shaft and pivot of the hammer so that the operative point 9 is located near such plane and close to the cage 21 with which it co-operates in reducing material. Y

Only the point 9 as shown and the corresponding cutting edge, is exposed while the other three points are protected by the recess from wear against the material until they are successively brought to the outwardv axis of said recess inclined backwardf-and lying in oylindri en insertA piece loosed in said recess and oonsising of i four-pointed piece having widened ends and a. reduced body portion and litting seid recess-one of said points being exposed in operative position and projeoing beyond die front jaw and located near the said radial plane.

2. in a rotary pivoied liaininer, e reversible insert piece having two symmetrical dove-'mil ends connected by a redwood bodyv portion forming Vwo Vpairs of en i poin e-iL zi-disjnn lie eenier of ilie pio lie edgeA suroi' the l," and ends oel ,l nes @ging both Ways from lie mit die o *die body und ineeingthe end edge sur-'faces in :were :ingles forming four cutting poinl's,a correspond ing recess being provided in 'lie heed end of the lmnnner exposing one of said Cutting edges in operative position, and means for merels securing seid insert' piece nrsfi... ably in seid recessy substant scribed.

3. In e.` rotary pivoted liannner, a reversible insert piece consisting of two sjfnnnecriool dove-teil end portions conneeed by a reduced body portion,-eficli end porion having' tiro ing edge surfaces and an end surface bien meet in ecute :ingles hereby forming cutting edges equidistent from die @renier of the said piece, the edge surfaces being;r adapted to 'form snecessi'vely die fronttln f cutting edOe when enoli point oi tbe adir ofd 23 A .L

dove-fails is adjusted successively io operaitivev position in a lninnner.

In testimony Wliereo l lieve eil'xed my signature.

HAROLD M. PLAISTED. 

